1. Field of the Invention
The present invention relates to closed captioning, and more particularly to control of various aspects of closed captioning by other than the captioner.
2. Description of Related Art
A video caption is a title, short explanation, or description that typically accompanies a pictorial work, and in particular a video work. Open captions are always visible to the viewer while closed captions are visible to the viewer upon activation of a suitable decoder. Closed captioning includes the type of captioning governed by 47 C.F.R. §15.119. Captions may be imposed on a video signal live as the signal is generated, or during post-production of the work. Live closed captioning, which is commonly done for any live programming such as televised news programs and sports events, typically uses text created in real time as the video program is broadcast, or a combination of real time text and prepared script. Real time captioning typically involves a captioner who writes the caption as it is broadcast using any suitable text entry technique.
A stenocaptioner is a specific type of captioner who uses a shorthand keyboard to enter phonetic shorthand into a computer, which translates the phonetic shorthand into characters (letters, numbers, symbols and spaces) in the desired language and communicates the characters and various control codes typically to a program originator using a modem. The program originator, which typically is a broadcast station, a cable operator, a municipality, an audio-visual educational presenter, a public access originator, a satellite uplink station, and so forth, encodes the video carrying the program with the caption using a specific type of encoder known as a closed-caption encoder. Closed caption encoders are well known in the art, and include the various models of SmartEncoder encoder and the model EN470 encoder, which are available from Computer Prompting & Captioning Co. of Rockville, Md.
The closed caption encoded program ultimately is received by a viewer. The closed caption is not visible on the viewer's television screen unless the viewer uses a closed-caption decoder. Such decoders are well known in the art.
An example of a conventional system for performing real time closed captioning at a broadcast station is shown in FIG. 1. The captioner typically writes the caption using a shorthand keyboard 102 that is cabled to a personal computer (“PC”) 100. The captioner PC 100 typically is a general purpose computer running a suitable captioning application software such as the TurboCAT software available from Cheetah International, Inc. of Tucson, Ariz. The resulting caption data, which is a combination of caption characters and control data, typically is transmitted to an encoder 132 typically located at a broadcast station using any desired transmission agency. The transmission agency shown in FIG. 1 is a direct modem-to-modem transmission agency using, for example, respective modems 112 and 130 and a dial-up connection 120 to maintain a direct modem-to-modem connection. Although shown as a separate device in FIG. 1, the modem 130 may be incorporated in the encoder 132. The caption data is added to the video signal by the encoder 132, and the video signal is combined with audio (not shown) and transmitted using a transmission agency such as conventional radio frequency (“RF”) broadcast 134, cable or satellite transmission (not shown), and so forth. The transmission containing the video signal and the caption data is received by the viewer's viewing device, a popular example of which is an standard television set 140 which includes a decoder that decodes the transmission and displays the caption on the viewer's screen along with the video work. All television sets of a certain size produced in the United States or imported into the United States must have a built-in decoder and decoder controls.
Typically, closed captions for video works are inserted into the line 21 blanking interval, and upon being decoded give the impression that they are part of the picture. The default placement for closed captions tends to be the two or three lines at the bottom of a video screen, although known captioning software allows a captioner to select the number of lines and the placement of those lines on the video screen. Unfortunately, the size and location of the closed caption typically cannot be specified at the broadcast station, which can result in some portion of the picture becoming blocked and invisible to the viewer under certain circumstances. For example, severe weather notifications and news flashes may from time to time appear in the picture as a type of open graphic known as a banner in the same area of a video screen as closed captions. If the closed captions are not moved elsewhere or suppressed, the banner will be blocked from full view. FIG. 2 shows a normal video of a news conference during which a sever storm warning banner is displayed at the bottom of the screen. Closed captioning is turned off. FIG. 3 shows the same news conference being viewed with closed captioning turned on, just prior to display of the severe storm warning banner. The speaker is saying “Just one more question, please. I will take the next question from Mr. Smith.” A two line caption accurately capturing this statement appears at the bottom of the screen. However, at the next instant the station displays the sever storm warning banner at the bottom of the screen, as shown in FIG. 4. While this may be done in a variety of different ways, one common technique is to merge a video of the banner with the main video to create a composite video signal for display. Unfortunately, as can be seen by comparing FIG. 4 with FIG. 2, the caption obscures much if not all of the warning banner, thereby denying the viewer notification of critical information.
Some closed captioning encoders include the capability of automatically repositioning a closed caption a predetermined number of lines upon receipt of a signal from the Emergency Alert System. However, the program originator has no control over this repositioning function except to activate or deactivate it, and the repositioning function is ineffective on other types of open graphics.
While the broadcaster could try to telephone the captioner and instruct the captioner to resize and/or relocate the caption in anticipation of the banner, the captioner usually is entirely focused on transcribing the oral material and would be unlikely to answer the telephone. Similarly, the captioner likely would not be closely monitoring the televised image while performing a transcription, since such close monitoring would be a distraction. Moreover, even if the captioner were to monitor the televised image to detect the appearance of a banner message and to reposition the caption accordingly, the banner message would still be obscured for the time required for the captioner to notice the message banner and enter the repositioning instructions. Hence, a need exists for a way to reposition the caption more or less contemporaneously with the display of a message banner, without disrupting the captioner's transcription of the oral content of the audio-video work.